Posted by widyan on Saturday, January 21, 2012 at 1:43am.
Timothy had a total of 238 blue and red marbles. He gave 3/7 of the blue marbles and 5/8 of the red marbles away. Altogether, Timothy gave away 124 marbles.How many red marbles did Timothy give away? (Skill: Equations)

mathematics  drwls, Saturday, January 21, 2012 at 2:10am
B + R = 238
3B/7 + 5R/8 = 124
Multiply both sides of the last equation by 8/5.
24B/35 + R = 198.4
Subtract the above equation from the first one.
11B/35 = 39.6
Multiply both sides by 35/11
B = 126
R = 112 is the number of red marbles. 
mathematics  kitty, Monday, September 22, 2014 at 1:48pm
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